Plot at its finest. He even made chakra arms later and was able to manifest nine tails and maintain them for the alliance to hold onto.
Another rubbish plot moment is that Minatos marking on Obito disappeared. At first I thought it made sense because he got a new body. However that wasn't the case, his original body was just covered in a new layer, but his original body still remained underneath the Juubi skin layer. So why the mark disappeared makes no sense at all. Even Kakashi who stabbed Obito through the marking, yet the mark still remained.
And then Onmyoudon only comes into play when minato goes up against against Obito but not the other Hokage's. To say it was all plot would be an understatement. Not only was he trolled, he was handicapped as well.